Attachments to lift trucks are often added to a standard carriage that normally carries the lifting forks. This offsets the position of the lifting forks an additional distance from the front axle of the lift truck, reducing the lifting capacity of the lift truck.
A simplified approach to integrating a lift truck scale into a lift truck lifting structure is to rigidly attach some of the parts that are normally included within the fork lifting carriage assembly to the scale assembly. This provides only a marginally accurate scale that is sensitive to the lift truck load bearing structures flexibility.
Accurate scales are simply (not rigidly) attached to a lift truck so that deformations or deflections of the lift truck do not distort the scale causing it to be inaccurate. This is the nature of the nested lift truck attachment design. This nested attachment also makes the replacement or removal and repair to the attachments such as a lift truck scale similar to the hang-on type.
Prior art lift truck scales are provided by many manufactures such as Avery Weigh-Tronix, LTS, Allegany, Filing Scale Company, Rice Lake, Intercomp, MSI Scales and Bilanciai. These are examples of scales that simply hang on the lift truck in the location that the forks originally were located.
Another arrangement by Mettler Toledo provides an integrated scale, which is disclosed in Rice et al., U.S. Pat. No. 7,026,557. This scale is built into the lift truck lifting system with compensation for drag forces. The removal of the scale is very difficult and repairs to the scale are repairs to the lift truck.
Accordingly there is a need for an attachment for devices to be mounted to a lifting mechanism that reduces the horizontal off set distance. Desirably, such a device provides easy installation and removal. More desirably, such a lift truck carriage is provided that allows the attachment to nest within the lift truck carriage to reduce the loss of position by the thickness of the normal lift truck carriage thickness.